Electromagnetic apparatus



4 Sheets-Sheet l H. A. HENNING ELEGTROMAGNETIG APPARATUS Filed March 14, 1959 Oct. 22, 1940.

/NVENTOR H. A. HE NN/NG BY ATTORNEY Oct. 22, 1940. H4 A. HENNING 2,213,609

ELECTRO/MAGNETIC APPARATUS Filed March 14, 1959 4 Sheets-Sheet 2 ATTORNEY Oct. 22, 1940. H A, HENNlNG 2,218,609

ELECTROMAGNETIC APPARATUS Filed March 14,' 1939 4 Sheets-Sheet 3 24 co1. L Ec r /Nl/E/vroR By HA. HENN/NG mgm/w Ar'roR/s/Ex Oct. 22, 1940. H. A. HENNING 2,218,609

ELECTROMGNETIC APPARATUS Fled March 14, 1959 4`ShSetS-She8t 4 REFUND VEA/TOR y H. A. HENN/NG www A T TOR/'VE V Patented Oct. 22, 1940 UNITED STATES PATENT OFFICE ELECTROMAGNETIC APPARATUS Application March 14, 1939, Serial No. 261,696

13 Claims.

' This invention relates to electromagnets particularly of a type suitable for use in telephone coin collectors.

An object of the invention is to improve the eiiiciency of electromagnets and simplify their construction in securing a selective operation of their armatures depending upon the polarityv of the voltage applied thereto.

The electromagnet of this invention is of particular value in the operation of telephonecoin collectors wherein the subscriber tentatively deposits a coin which is placed under control of the central oiiice and is subsequently collected or refunded, depending upon whether the desired telephone connection is obtained. Thus in the type of telephone coin collector disclosed in the O. F. Forsberg U. S. Patent 1,043,219, issued November 5, 1912, the coin deposited by the subscriber is temporarily held upon a coin trap which is supported by a pivoted vane under the control of an electromagnet. If the pivoted vanev is moved by the electromagnet in one direction the deposited coin is collected, while vif it is moved in the opposite direction the coin is refunded and the direction the vane is moved depends upon the polarity of the applied voltage. For producing such a selective actuation to control coin collection or coin refund, an electromagnet is required which is capable of eicient operation 740 over a wide variation in energizing current and' load.

This invention as applied to telephone coin collectors of the above type preferably comprises a single coil electromagnet. The armature for the electromagnet has Va lateral extension. to which is pivoted a depending member carrying a permanent magnet located in the field of the electromagnet so that the depending member is deflected laterally in a direction dependent upon 40 the polarity of the voltage applied to the winding. This depending member will therefore be elevated whenever the armature isV attracted and at the same time will be deiiected laterally in a direction defining the polarity of the applied 45 voltage. 'I'he lower end of the depending member may comprise a cam type latch for engaging Fig. 1 is a view partly in section of the centrall portion of a telephone coin collector; y

Fig. 2 is a circuit schematic of a coin collector substation; 55 Fig. 3 is an end view partly in section o f the electromagnet of this invention associated with a coin hopper;

Fig. 4 is a front view of the apparatus of Fig. 3;

Fig. 5 is a top View of the apparatus of Fig. 4; 5

Fig. 6 is a side view of the electrical spring contacts which control the energizing circuit for the associated electromagnet;

Fig. '7 is similar to Fig. 4 except that the electromagnet is shown energized to cause a discharge 10 of any deposited coin into a collect chute;

Fig. 8 is a side view of the electrical spring contacts and associated parts in positions reached by the energization of the electromagnet as in Fig. 7; '15

Fig. 9 illustrates the essential portion of the apparatus of Fig. 4 when the electromagnet has been energized to discharge any deposited coin into a refund chute;

Figs. 10 and 11 are enlarged views of the cou- 20 pling mechanism between the armature of the electromagnet and the coin vane shown in normal and operated positions, respectively;

Fig. 12 is a sectional View along the line |2l2 of Fig. 10; and 25 Fig. 13 is a sectional view along the line I3-l3 of Fig. 10.

The above drawings do not disclose a complete telephone coin collector but the general construction of one form of such a collector with which Ithis invention may be employed may be ascertained by reference to the O. F. Forsberg U. S. Patent 1,043,219.

As disclosed in the Forsberg patent, a person wishing to use a telephone coin collector inserts a coin in a coin gauge and the deposited coin after traversing a coin chute I5 for testing its genuneness and striking a suitable coin signal drops into a coin hopper I6 and comes to rest upon a coin trap ll which extends across the l coin passageway. The trap Il which is shown pivoted at the point i8 has a counterweight I9 and when it carries a coin load is supported by a roller 20 on a vertical coin vane 2l pivoted at its lower end. The coin passage below trap I 'l 45 is divided into two coin channels, a refund chute 22 leading to an opening Where coins are ac'- cessible from outside the collector housing 23, anda collect chute 24 leading to a cash compartment within the housing. As explained in the Forsberg patent,.if the vane 2l is moved to close the collect passageway 24 the dropping of .trap I'l'will allow the deposited coin to fall into refund chute 22 while if the vane 2| is moved to close the refund passageway 22 the dropping of 55 trap I1 will allow the deposited coin to fall into 4collect chute 24. The apparatus so far described is similar to that disclosed in the Forsberg patent.

The invention in the embodiment shown in the drawings is concerned wi-th the provision of improved means whereby the operation of vane 2| may be remotely controlled to collect or refund a deposited coin depending upon whether ornot the desired telephone connection is secured.

Suitably mounted on lugs 21, 28 of tray 25 and adjacent the coin hopper I6 is an electromagnet comprising a single coil 26 surrounding a core of soft iron or other suitable material. A U- shaped strip 29 of magnetic material surrounding the 'top and the ends of the coil Acompletes the main magnetic circuit except for the armature 36 which is pivoted about axis 3|. Armature 36 is U-shaped in cross-section having a iiat face adjacent the core and a fiat portion parallel to and closely adjacent each of the plates 32, 33 of the return path 29. An auxiliary return path for -f the magnetic uxis provided by arm 34 fastened tothe core at the armature end thereof and arm 35 extending from the U-shaped member 29 at the opposite end of the core. The adjacentrends of these two arms 34, 35 are separated by an air-gap for a purpose to be described later.

Suitably fastened to armature 30 is a laterally and upwardly extending arm 36 to an intermediate portion of which is fastened the armature biasing spring 31. Arm 36 also carries a stud 38 which on its upward travel due to armature at' traction picks up an additional armature restoring spring 39. Freely pivoted on extension 36 is a" depending arm 46 which carries a small permanent bar magnet 4| the lower end of which lies centrally in the air-gap between the ends of arms 34, 35. The extreme upper end of arm 36 has an insulating stud 42 for controlling the electrical spring contacts in a manner to be described later.

Suitably supported between spaced portions 49 and 56 of the bottom plate 43 of the coil supporting structure is a stationary rod 44 about which is rotatably mounted a framework comprising two cross-pieces 45, 46 which are centrally apertured to receive rod 44. These two cross-pieces are rigidly united by two spaced pins 41, 48 which lie on opposite sides of rod 44 with the two pins and the rod normally lying in a substantially horizon-v tal plane as shown in Fig. 10. The cross-bar 46 has an upwardly extending arm 5| which has a fork 52 at its upper end to receive the coin vane pin 53 which projects through the arcuateslot 54 in the `adjacent coin hopper side wall.

Depending armterminates in a cam type latch comprising a pair of spaced jaws 55, .156i` which embrace the pins 41, 48 with pin 41"nor mally lying against cam vsurface 51 and pin '48 lying against cam surface 58. Intermediate .its

cam surfaces 51, 58 the arm 46 has a hollowedout portion 59 to avoid contact with the stationary rod 44. These pins 41, 48 act as a stop for the armature in its non-operated position since the downward pull of spring 31 on arm 36 causes a downward thrust on depending arm 46 to vnormally maintain cam surfaces 51, 58 against the electromagnet cannot be energized until elecy -trical spring contacts 6| and 62 have been closed to connect 'one terminal of the winding to ground. However, these contacts may be closed by the deposit of a coin in the collector.v Any deposited coin before coming to rest on coin. trap |1 strikes v a coin trigger 63 and causes the coin trigger the coin actuation of trigger` 63' lifts shoulder 66 out of the path of spring end 65 as in Fig. 6

thereby allowing biasing spring 64 to move free- 1y to the left to closethe contacts. Thereafter and at the proper time a suitable switchingmeans 61 at'the central oflice (FigpZ) may be lactuated to connect either positive or negativebattery to winding 26 depending upon whether coin: refund or coin collection is desired.

As long as the electromagnet is deenergized, the various'movable parts occupy their normal positions of Fig; 4 but as soon as battery is applied to the electromagnet the armature is attracted from lits position of Fig. 4 to its position -as rin Fig. 7 whereit lies against stop 68. At the same time permanent'magnet 4| which lies in the stray magnetic field between pole extensions 34 and 35 will be attracted towards arm 34 or arm 35 depending upon the polarity of the applied voltage. If the applied voltage is of one polarity, arm 46 is moved about its pivot 69 to the right as seen in Fig. 11 tending to bring vertical edge 16 of jaw 55 against pin 41; or if the applied voltage is of the opposite polarity, arm 46 is moved laterally towards pole extension 34 tending to bring vertical edge 1`| of jaw k56 against pin 4 8.

At the same time that arm 46 is being moved laterally due to the reaction between permanent magnet 4| andthe stray magnetic eld, the said arm 46 will also be moved upwardly by the attraction of armature 36. However, the small lateral movement required of arm 46 is substantially completed before there has been an appreciable upward movement of arm 46 and if we assume that the lateral movement has been such as to attract edge 16 towards pin 41 the subsequent lifting of arm 46 will bring the horizontal surface 12 into engagement with pin 41 thereby moving pin 41 upwardly and pin 48 downwardly of jaw 55 the opposing jaw 56 lies outside the downward path of pin 48. The completed movement of the pins 41 and 48 is shown in Fig. 11 for v an applied voltage of one polarity and shows that Y Y the frame structure comprising pins 41 and 48.v`

has been moved clockwise through an angle of about 25 degrees.

On the other hand if the applied voltage is such that the permanent magnet is attracted towards pole-piece 34 tending to bring vertical edge 1| of jaw 56 into engagement with pin 48 the resulting upward movement of arm 46 by armature attraction will cause the horizontal shoulder 123 to engage pin 48 and throw pin 48 upwardly since the other jaw 55 will not lie in the path of pin 41; and upon the completion of this counter-clockwise movement pins 41, 48 will lie in positions just the reverse of that shown in Fig.

11. As previously stated, spring 31 for the unoperated position of the armature holds the opindicated in Fig. 16. Forces due to the reaction "9117116 bil-passed ux and the permanent magnet 'since with pin 41 embraced by portions 16, 127 v posed cam surfaces 51, 58 against pins 41, 48 ras aaiaooo 4| do not, therefore, produce lateral motion of the magnet arm 48 until due to the main armature motion the cam 85, 58 has been disengaged from the two pins.

It, therefore, follows that the structure which comprises cross-bars 45, 48 with interconnecting pins 41, 48 will be moved clockwise or counterclockwise about its axis 44 depending upon the polarity of the applied voltage; and since arm 5| constitutes a part of this rotatable frame structure it follows that for an applied voltage of one polarity, coin vane 2| will be moved counterclockwise to its coin refunding position of Fig. 9 and for an applied voltage oi' the opposite polarity coin vane 2| will be moved clockwise to its coin collecting position of Fig. 7.

It will be apparent from the showing in Fig. 10 that if the arm 40 should be moved upwardly by amature attraction without any lateral movement, cam surfaces 12 and 13 would strike pins 41 and 48 simultaneously, whereupon the upward movement would cease without producing any rotative movement of the vane controlling arm 5I. But the arrangement of the parts is such that only a slight lateral movement of arm 48 in one direction or the other is needed to have only one of these cam surfaces contact with its associated pin, thereby producing the desired rotative movement. As previously pointed out both the horizontal and vertical forces actuating on cam 55, 58 actuate simultaneously and both components of attraction enter into the resulting cam stroke. However, it is not necessary to exhaust the horizontal component of the cam before establishing a vertical driving contact. In the preferred embodiment, a very small horizontal motion of the cam type latch 55, 56 is suflicient to start the proper selection of pin 41 or 48. In the very rare event that the horizontal motion is not completed before surface 12 or 13 strikes pin 41 or 48, then the opposite surface 11 or 18 combined with the strong vertical pull from the amature completes the horizontal selection.

The cam type latch 55, 58 furnishes the impor-.- tant control point in the design of the relay. Its design permits the use of one restoring spring 31 which restores the armature and the trap vane for either collect or refund. 'I'he latch is also so designed that the initial movement of the armature can be made independent of the coin load and thus controlled by the restoring spring 31 alone. To some extent the contours of the cam surfaces of the latch member 55, 58 can be used to control the amount of pull exerted by the armature during the entire stroke so that the optimum forces can be obtained at the desired points of the stroke. While the pins 41, 48 are shown integral with arm 5| and the cam surfaces are shown cut in the lower end of arm 48, it is obvious that these parts may be reversed with the pins attached to link 40 and the cam surface cut in a plate attach ed to arm 5|.

Regardless of the polarity of the applied voltage the resulting upward movement of amature extension 36 raises the insulating stud 42 carried thereby and the upward movement of this stud acting against the angular portion 14 of spring 8| causes the spring pile-up 6|, 82, 64 to be moved to the right far enough to free the coin trigger of spring projection 85 thereby allowing the coin trigger to restore to normal under the action of its counterweight 15, as shown in Fig. 8. In Fig. 8, it is assumed that the electromagnet is still energized with stud 42 maintaining the spring pile-up in such a position that spring projection 8l is out of engagement with trigger shoulder 88. As soon as the electromagnet has been deenergized the downward movement of arm 38 allows the spring pile-up to move to the left until projection 85 engages shoulder 86 whereupon the electrical contacts are in their normal open position.

In view of the above description it is believed that there will be no difficulty in following the various operating steps shown in the various figures. In Figs. 3, 4 and 5 all parts are in their normal positions with the electromagnet deenergized and the coin trigger non-operated. In Fig. 6 the coin trigger has been dropped by coin deposit to close the electrical contacts but the electromagnet has not yet been energized. In Figs. 7 and 8 the electromagnet has been energized by voltage of such polarity as to cause the coin trap to discharge its coin load into collect chute 24, while in Fig. 9 the electromagnet has been energized by a voltage of the opposite polarity to cause the coin trap to discharge its coin load into refund chute 22. f

As previously stated the armature 38 is biased to its normal position by coiled spring 31 but after the armature has moved through the initial portion of its path, stud 38 on arm 38 picks up spring 39 which provides an additional restoring force for the armature when the source of energizing current is disconnected from winding 28. It is also obvious that the coin vane load is not coupled to the armature until after the armature has moved a short distance from its normal position. Both of these features contribute in reducing the load carried by the armature in its initial movement and hence aid in meeting the close margin between the operate and non-operate requirements of a coin collector relay. In

one embodiment of the invention the electromagnet operated with a minimum applied current of .045 ampere which value was independent of the coin load, it would not operate with an applied current of .041 ampere, and would release with an applied current of .031 ampere. Spring 39 provides the necessary adjustment to meet the release value just given.

It should also be noted that the main magnetic circuit of the electromagnet of this invention is not polarized by a permanent magnet but is a simple electromagnet towards which the arma- -ture 30-is always attracted regardless' of the direction of the operating current. Leakage ux from the main magnetic circuit is used to react upon an auxiliary permanent magnet of extremely small size, which through a cam type latch permits the armature to actuate the coin trap vane in one direction or the other depending upon the direction of current in the main magnetic circuit winding.

What is claimed is:

1. In combination, an electromagnet comprising a core, an energizing winding on said core, a movable member comprising a permanent magnet, means controlled by said electromagnet for moving said permanent magnet about one axis in a direction independent of the polarity of the voltage applied to said winding, means for moving said magnet about a different axis in a direction dependent upon the polarity of the applied voltage and means selectively controlled by the resultant movement of said member.

2. In combination an electromagnet comprising a core, an energizing winding on said core, a movable member comprising a permanent magnet, means controlled by said electromagnet for moving said permanent magnet about one axis in a direction. independent of the polarity of the volta-ge applied to said winding, means for moving said magnet about a different axis in a direction dependent upon ,the polarity of the applied voltage, a rotatable member, and means responsive to the resultant movement of said iirst member to rotate said rotatable member in a direction dependent upon the polarity of the voltage ap plied to said winding.

3. In combination, an electromagnet comprising a core, an energizing winding on said core, a movable member comprising a permanent bar magnet mounted adjacent said electromagnet, means located in the field of said electromagnet for moving said permanent magnet about an axis in a direction independent of the polarity of the voltage applied tosaid Winding, other means located in the field of said electromagnet for moving said permanent magnet about a diierent axis in a direction dependent upon the polarity of the applied voltage, and means selectively actuated by said member in accordance with the polarity of the voltage applied to said winding.

4. In combination, an electromagnet comprising a core, an energizing winding on said core, a member pivotally mounted for rotative movement about a iixed axis, an arm pivoted to said member and comprising a permanent magnet, means controlled by said electromagnet for moving said member about said axis in a direction independent of the polarity of the voltage applied to said winding, other means for deflecting said arm in a direction dependent upon the polarity of the voltage applied to said winding, and means selectively actuated by said arm in ac- `cordance with the polarity of the voltage applied to said winding.

V5. In combination, an electromagnet comprising an energizing winding, a non-permanently magnetized armature mounted for movement about one axis, an arm pivotally mounted on said armature about an axis parallel to said rst axis, a permanent magnet mounted on said arm and located in the field of said electromagnet whereby said arm is deected in a direction dependent upon the direction of current iiow through said winding, and means selectively actuated by said arm.

6. In combination, an electromagnet comprising a core, an energizing-winding on said core, a non-permanently magnetized armature for said electromagnet pivotally mounted for rotative vmovement about a certain axis, said armature having an extension extending substantially parallel to said core, an elongated member pivotally mounted at one end to said extension and comprising a permanent magnet located in the eld of said electromagnet, and means selectively actuated by said member.

7. In combination, an electromagnet having a core, an energizing winding for said core, a non-permanently magnetized armature mounted for movement about one axis adjacent said core, an arm'pivotally mounted on said armature and comprising a permanent magnet located in the iield of said electromagnet whereby said arm is deflected in adirection dependent upon` the polarity of the voltage applied to said winding and is moved in another direction by the attraction of said armature, a rotatable member, and means responsive to the resultant movement of said arm for rotating said rotatable member in a direction dependent upon the polarity of the voltage applied to said winding.

Lmagnet-located in the iield of said electromagnet whereby said member is deflected laterally in accordance with the direction of current ilow through said electromagnet, and means selectively actuated by said member.

9. In combination, an electromagnet having a non-permanently magnetized armature pivoted' about a substantially horizontal axis, said armature having a laterally extending portion, a downwardly extending arm pivoted at its upper end to said portion and comprising a permanent magnet located in the eld of said electromagnet whereby said arm is deected about its pivot when said electromagnet is energized, and said arm is moved longitudinally when said armature is attracted by said electromagnet, and means selectively actuated by said arm. 4

10. In a telephone coin collector, an electromagnet having an energizing winding and a nonpermanently magnetized armature pivoted -about a substantially horizontal axis, said armature having a laterally extending portion which is moved upwardly when said armature is attracted by said electromagnet, a downwardly extending arm pivoted to said portion and carrying a permanent magnet located in the field of said electromagnet whereby said arm is deected laterally in accordance with the polarity of the voltage -applied -to said winding, a rotatable member, and coupling means between said member and said arm to cause rotation of said member in a direction dependent upon the polarity of the voltage applied -to said winding.

11. In a telephone coin collector, an electromagnet having an energizing winding and a nonpermanentlyvmagnetized armature pivoted about a substantially horizontal axis, said armature having a laterally extending portion which is moved upwardly when said armature is attracted by said electromagnet, a downwardly extending arm pivoted at its upper end to said portion and carrying a. permanent magnet located in the ield of said electromagnet whereby said arm is deflected laterally in accordance with the polarity of :the voltage applied -to said winding, a bar mounted for rotation about a iixed axis, and spaced pins on sa-id bar, said arm having spaced ngers for engaging one ofV said pins when the applied voltage is of one polarity and for engaging the other of said pins when the applied voltage is of the opposite polarity to rotate said Ibar in a direction dependent upon .the-'polarity of the applied voltage.

12. In combination, an electromagnet having an energizing winding, a non-permanently magnetized armature pivoted for rotative movement about a xed axis, said armature having a substantially horizontally disposed extension, a depending arm pivoted at its upper end to said extension and comprising a permanent magnet located in the field of said electromagnet where- Iby said arm is raised when voltage is applied to said winding and at the same time is-deeoted about its pivot in a direction determined -by the polarity of the applied voltage, a member mounted for rotation about axed axis, and coupling means between said arm and said member for rotating said member in a clockwise direction when the applied voltage is of one polarity and for rotating said member counterfclockwise when the applied voltage is of the opposite polarity.

13. In combination, an electromagnet having a non-permanently magnetized armature pivotally mounted about a substantially horizontal axis, said armature having a laterally extending portion, a downwardly extending arm pivoted at its upper end to said portion and comprising a permanent magnet located in the iield of said eleotromagnet, arotatable pin bar carrying two spaced pins located on opposite sides of the axis about which said bar is rotatable, and a cam type latch on the lower end of said arm for engaging one oi' said pins to cause a clockwise rotation of said lbar when the voltage applied to said electromagnet is of one polarity and for engaging the other 'of said pins to cause a. counter-clockwise rotation of said bar when the applied voltage is of the opposite polarity.

. HARLEY A.. HENNING. 

